1. Field of the Invention
The present invention relates to a method of constructing multi tomographic image, in which by storing frame images having whole subject images on the radius of gyration in the large-capacity frame image storage means with panoramic X-ray photographing of one time, and by performing the overlapping process of the frame images, the plural pieces of the frame images forming the tomography on the arbitrary radius of gyration are used to construct a tomographic image of the respective radii of gyration, on the arbitrary radius of gyration easily.
Moreover, the present invention relates to a digital 3 D X-ray photographing apparatus, in which a stereoscopic image can be formed by making the transversal slice images from the tomographic images of respective radii, and by using a volume rendering software.
2. Description of Related Art
As such kind of method of constructing multi-tomographic image and digital 3 D X-ray photographing apparatus, present applicant previously filed “Method of constructing multi-tomographic image and digital 3 D X-ray photographing apparatus” to Japan (refer to Japanese Patent Application No. 375011/2004).
In the method of constructing multi-tomographic image and a digital panoramic radiography apparatus of this prior application, as shown in the FIGS. 1 and 2, all X-ray photographed images at respective angles obtained at tomogram-photographing on the circular orbit are stored, after X-ray photographed, these X-ray photographed images are arranged on a circular arc at the radius place that becomes a reference, the tomographic images at a plurality of radius places are constructed, by adding while moving every shifting amount decided every tomographic image at each radius place. As for the tomographic image that can be obtained by the technique, the thickness of radial is limited to 0.5 mm, therefore, even if the fineness of the angular direction of the array of the circular arc (divided number) is increased, a great degree of mixings of pixel value in the periphery sections are generated (“δ” in FIG. 2), so that expressive power becomes weakened, accordingly, the number of partitions of the angular direction is also limited.